1. Field of the Invention
The present invention relates to a swinging gripper arrangement for sheet-processing machines, in particular, sheet-fed offset printing presses.
2. Description of the Prior Art
In known swinging grippers, for example in German Offenlegungsschrift 37 36 808, the grippers are fixed on a gripper shaft, the gripper shaft bearing a roller lever, the end-positioned roller of which is in contact with the outer edge of a cam segment. The gripper spring pulls the roller into a contact with the cam segment and is fixed at its other end on a roller lying opposite, the opposite lying roller being in contact with an equidistant inner cam of the cam segment and being seated on a roller arm which extends rigidly from the gripper rocker. The cam segment itself is swivelable about a pivot point against spring loading, the swivel motion being controlled by a feeler roller which rolls on a cam disc that is mounted coaxially with respect to the appropriate drum of the sheet-processing machine.
Such known devices may, in fact, reduce the vibrations occurring in the gripper system and thus diminish the occurrence of associated register errors. They are, however, not particularly well suited to optimally fulfilling all of the essential requirements of high-speed, high-performance printing presses. This has particularly been found to be the case in that the gripper spring itself must also be moved in line with the high-speed rhythm of such machines, with a significant role being played, not only by its mass, but also by the movement in space that occurs transversely with respect to the tensile force of the spring